The public_transport=stop_area tag is used as part of a relation to identify all of the features associated with a public transport interchange or part of one. A stop area for a simple bus stop with buses in both directions would consist of two waiting areas or shelters which can be tagged using (public_transport=platform and/or highway=bus_stop) and two stop positions (using public_transport=stop_position). More complex stop areas may include multiple platforms and stop positions and many associated elements.

For larger interchanges it is often appropriate to organise stop areas into a hierarchy. Heathrow Airport would for example consist of 5 terminals, a coach station and two underground stations with many associated facilities. A single stop area may include elements for many transport modes, including train, subway, monorail, tram, bus, trolleybus, aerialway and ferry. Some stop areas may also be identified as a public_transport=station.